The author of the text that contains this quote appeals to the reader's sense of logic by quoting an authority/expert on the matter. Taking into consideration that expert's opinions, in argument, are as close to a fact as you can get without actually using a fact, this shows us how your best answer here is option B.
<span>Insertion of one of two bases shifts the entire codon and changes all coding regions from there on out. Introducing three bases will place a new amino acid into the protein and can change the overall structure and binding regions, but it will for the most part be the same protein. Adding in those two will change every amino acid after that point, making it longer, shorter and possibly a completely new protein.</span>
A.) Activate Your Turn Signal